1. Field of Invention
This invention relates to the field of remotely piloted vehicles (RPVs) and unmanned aerial vehicles (UAVs). RPV is an older term for UAV. UCAV shall mean “Unmanned Combat Aerial Vehicle.” UCAV is also sometimes defined as an “Uninhabited Combat Aerial Vehicle.” UCAV is a UAV that is intended for use in combat. UAS means “Unmanned Aerial System.” UCAS means “Unmanned Combat Air System.” ROA means “Remotely Operated Aircraft.” The characteristics all these vehicles have in common is that there is no human pilot onboard and although they may be operated autonomously they can also be controlled by a remotely located operator or pilot. The term UAV shall be used as a generic term for such vehicles. “Synthetic Vision” is the current term for three dimensional projected image data presented to the pilot or other observer. Another term for “Synthetic Vision” is “Synthetic Environment.” An older term for “Synthetic Vision” is “Virtual Reality.” The term “Augmented Reality” (AR) refers to a human/computer interaction in which synthetic, computer generated elements are mixed or juxtaposed with real world elements in such a way that the synthetic elements appear to be part of the real world. A common method used by Augmented Reality systems is to combine and overlay a synthetic vision system with the video from one or more video or infrared cameras. Augmented Reality is also sometimes referred to as “Enhanced Vision.” The term “Remote Pilot” shall mean the same as “Remote Operator.” The term “Sense and Avoid” shall mean the same as “See and Avoid.”
2. Prior Art
The use of Synthetic Vision in flying a UAV is taught by U.S. Pat. No. 5,904,724 Method and apparatus for remotely piloting an aircraft issued May 18, 1999 to Margolin (the present Applicant) which is hereby incorporated by reference. From the Abstract:                A method and apparatus that allows a remote aircraft to be controlled by a remotely located pilot who is presented with a synthesized three-dimensional projected view representing the environment around the remote aircraft. According to one aspect of the invention, a remote aircraft transmits its three-dimensional position and orientation to a remote pilot station. The remote pilot station applies this information to a digital database containing a three dimensional description of the environment around the remote aircraft to present the remote pilot with a three dimensional projected view of this environment. The remote pilot reacts to this view and interacts with the pilot controls, whose signals are transmitted back to the remote aircraft. In addition, the system compensates for the communications delay between the remote aircraft and the remote pilot station by controlling the sensitivity of the pilot controls.        
The system by which an aircraft periodically transmits its identification, location, altitude, and bearing was taught by U.S. Pat. No. 5,153,836 issued Oct. 10, 1992 to Fraughton et al. and was materially adopted by the FAA as Automatic Dependent Surveillance-Broadcast (ADS-B). According the article Gulf of Mexico Helo Ops Ready for ADS-B in Aviation Week & Space Technology (Feb. 26, 2007, page 56):                By the end of 2010, FAA expects to have the ADS-B system tested and operationally acceptable for the NAS, with Houston Center providing services in the Gulf region. By 2013, all of the U.S. is scheduled to be covered with ground infrastructure.        
Current Practice
The current practice in flying UAVs in civilian airspace is typified by the report Sensing Requirements for Unmanned Air Vehicles by AFRL's Air Vehicles Directorate, Control Sciences Division, Systems Development Branch, Wright-Patterson AFB OH, June 2004, which relies on computer-intelligence to use sensors to sense and avoid other aircraft.
According to the presentation entitled Developing Sense & Avoid Requirements for Meeting an Equivalent Level of Safety given by Russ Wolfe, Technology IPT Lead, Access 5 Project at UVS Tech 2006 this had not changed as of Jan. 18, 2006. Access 5 was a national project sponsored by NASA and Industry with participation by the FAA and DOD to introduce high altitude long endurance (HALE) remotely operated aircraft (ROA) to routine flights in the National Airspace System (NAS). Access 5 started in May 2004 but when NASA withdrew its support (and funding) the Industry members decided not to spend their own money and Access 5 was dissolved at the end of 2005.
The presentation Integration into the National Airspace System (NAS) given by John Timmerman of the FAA's Air Traffic Organization (Jul. 12, 2005) essentially says that under current UAS Operations in the NAS UAVs should not harm other aircraft or the public. (Page 3: “While ensuring ‘no harm’ to other NAS customers and public”)
The article Zone Ready for Drone, Apr. 7, 2006, on the web site for the FAA's Air Traffic Organization Employees states that,                Since March 29, a temporary flight restriction . . . has limited access to the airspace along almost 350 miles of the border, expanding an earlier TFR near Nogales. The restriction is in effect nightly from 6 p.m. to 9 a.m., although that time can be expanded by issuance of a Notice to Airmen. Aircraft wishing to fly in the TFR when it is active must receive authorization from air traffic control prior to entry. Once in, pilots are required to maintain two-way communication with ATC and transmit a discrete transponder code.        
The reason for the TFR is to enable Predator UAVs to patrol the border. The article quotes Stephen Glowacki, a Systems Safety and Procedures specialist with the FAA's Air Traffic Organization as saying:                This is an extreme situation that has been presented to us,” states Stephen Glowacki, a Systems Safety and Procedures specialist with the FAA's Air Traffic Organization, stressing the nation's security. “We have been working with U.S. Customs and Border Protection to try and answer this situation.”        Inserting UASs into the National Airspace System is not a simple feat. According to Glowacki, the technology and certification that will permit unmanned aircraft to “see and avoid” other air traffic is still eight to ten years away. In the mean time, a carefully controlled environment is needed.        
The track record of current UAV systems shows two major problem areas:
a. The communications link between the UAV and the ground station is unreliable, even at short ranges.
A recent example is the December 2006 crash of Lockheed Martin's Polecat UAV. When it lost communications with the ground it deliberately crashed itself to avoid flying into civil airspace. (See the article Lockheed's Polecat UCAV Demonstrator Crashes in Aviation Week & Space Technology, Mar. 19, 2007, page 44.)b. Autonomous Mode is not always very smart.On Apr. 25, 2006 the Predator UAV being used by the U.S. Customs and Border Protection agency to patrol the border crashed in Nogales, Ariz. According to the NTSB report (NTSB Identification CHI06MA121) when the remote pilot switched from one console to another the Predator was inadvertently commanded to shut off its fuel supply and “With no engine power, the UAV continued to descend below line-of-site communications and further attempts to re-establish contact with the UAV were not successful.” In other words, the Predator crashed because the system did not warn the remote pilot he had turned off the fuel supply and it was not smart enough to turn its fuel supply back on. (Note that this is the same Predator discussed in the article Zone Ready for Drone previously mentioned.)